Bug suicide could reveal new antibiotic

Scientists have come to understand the mysterious behaviour of kamikaze bacteria, and they say it could help them develop new kinds of antibiotics.

Some bacteria seem to be suicidal - producing toxic chemicals that kill them as well as closely related individuals. This seemingly paradoxical behaviour has been puzzling for scientists trying to work out why this self-harming mechanism would evolve in the first place. Now a team, led by Omar Cornejo from Emory University in Atlanta, think they have found the answer.
Despite killing its own creator the toxin provides an overall survival advantage, by preventing other bacteria of the same, or similar, species from invading the population. The key is that the invading organism is harmed to a greater extent than the toxin-producing population - keeping the invaders at bay. So even bacteria, say the authors, seem to follow the adage that you can win if you harm others to a greater extent than you harm yourself. 
The team looked at the common bacterium Streptococcus pneumoniae (pneumonococcus) which causes diseases such as pneumonia and meningitis in humans. Their conclusions were based not only on extensive culture experiments but also computer models.
Perhaps the most important finding is that pneumonococcus hasn't evolved to protect itself against these poisons. Resistance of bacteria to medicines that kill them antibiotics is a huge problem in current medicine. If bacteria are unable to evolve resistance to these toxins, they could be used to develop a new kind of antibiotic which overcomes this issue.